<!DOCTYPE html>
<html lang="en">
<head>
      <meta charset="UTF-8">
      <meta http-equiv="X-UA-Compatible" content="IE=edge">
      <meta name="viewport" content="width=device-width, initial-scale=1.0">
      <title>Document</title>
      <link rel="stylesheet" href="./css/index.css">
</head>
<body>
      <h1>hello sass</h1> 
      <div id="box"></div>
      <div id="box2"></div>

      <button class="btn-large">大按钮</button>
      <button class="btn">按钮</button>
      <button class="btn-small">小按钮</button>

      <div class="pox"></div>
      <div class="pox-small"></div>
      <div class="pox-large"></div>

      <ul id="list">
            <li> <span>hello</span> <strong>world</strong></li>
            <li> <span>hello</span> <strong>world</strong></li>
            <li class="active"> <span>hello</span> <strong>world</strong></li>
            <li> <span>hello</span> <strong>world</strong></li>
            <li> <span>hello</span> <strong>world</strong></li>
            <li> <span>hello</span> <strong>world</strong></li>
      </ul>
</body>
</html>